In order to increase the throughput of cells and coordinate interference among cells, new generation wireless communication systems, such as Long-Term Evolution advance (abbreviated as LTE-Advance) system, International Mobile Telecommunication advance (abbreviated as IMT-Advance) system, etc., all introduce the Coordinate Multipoint Transmission and Reception (abbreviated as COMP hereafter) technology at network levels.
Two kinds of reference signals of the LTE-Advanced are defined at the 56th conference of 3GPP LTE: channel measurement reference signal (abbreviated as CSI-RS hereafter) and demodulation reference signal (abbreviated as DMRS hereafter), wherein the channel measurement reference signal is clearly defined as cell-specific, and relatively speaking, the channel measurement reference signal is distributed more sparsely on time frequency resources.
However, how the channel measurement reference signal works in the LTE-A system and its mapping rules are not defined in details.